[Effect of daily intake of carbohydrate, protein and fat on serum levels of HDL cholesterol and apolipoproteins A-I and A-II].

To investigate the effects of daily ingested nutrients on serum levels of HDL constituents, amounts of daily food intake for three consecutive days were measured and serum levels of HDL-cholesterol and apolipoproteins A-I (abbreviated as apo A-I) and A-II (abbreviated as apo A-II) were determined for 48 subjects living in a local community.Mean HDL cholesterol level was significantly lower in type IIB (46.8±8.3mg/dl, p<0.05) and IV (40.9±9.9mg/dl, p<0.001) hyperlipoproteinemics, accompanied with hypertriglyceridemia, than in normolipoproteinemics (56.4±8.8mg/dl). However, the apo A-I levels were the same as normal (146.8±14.7mg/dl) and apo A-II levels, higher in types IIA and IV than in normal. These findings suggest a different response of lipid and protein parts of HDL to ingested carbohydrates.HDL cholesterol had a significant negative correlation to the amount of carbohydrate (r=-0.29, p<0.1) and protein (r=-0.34, p<0.05) daily ingested. Apo A-I and apo A-II had a significant negative correlation with carbohydrates (r=-0.51, p<0.01 and r=-0.31, p<0.1, respectively). However, when the intake of nutrients were expressed with the adequacy rate (amount ingested/amount recommended), which were adjusted for differences in individual sex, age, bodily constitution, and work load, HDL cholesterol lost the significant negative correlation with carbohydrate while apo A-I and apo A-II still retained or increased it.Excessive intake of carbohydrates has been known to accelerate the catabolism of HDL. In our study, it was shown that the increase of daily carbohydrate intake within a normal range mainly decreased the serum apo A-I and A-II levels. Considering the function of HDL in removing cholesterol from peripheral tissues, it was suggested that the intake of carbohydrates might have important effects on the genesis and prevention of atherosclerotic diseases by affecting the constitution of HDL.